The advent of disposable plasmid DNA miniprep kits has revolutionized molecular biology by enabling rapid and inexpensive plasmid purification. While affinity tags for protein purification have been developed, no currently available affinity tag enables rapid, inexpensive protein purification without requiring expensive, specialized reagents (e.g., immobilized binding substrates, immobilized antibodies, nickel nitrilotriacetate resins, etc.).